Shahzad Akbar, a legal fellow with the British human rights group Reprieve and the director of the Pakistan-based Foundation for Fundamental Rights, says the state department is preventing him from taking his clients to Capitol Hill next week. The hearing would mark the first time US lawmakers heard directly from drone strike survivors.

Akbar’s clients, Rafiq ur-Rehman, his 13-year-old son, Zubair, and his nine-year-old daughter, Nabila, are from the tribal regions of north Waziristan. The children were injured in the alleged US strike on the village of Tappi last year. Their grandmother – Rehman’s mother, Mamana – was killed.

Rehman and his children have spent months making preparations to visit Washington after being invited by US representatives to testify in the ad hoc hearing on drone strikes.

According to Akbar, his clients’ visas for the trip have been approved, but his has not. He believes the hold-up is political.

House Rep. ALan Grayson (D-FL), who was assisting the Rehman family coming to the US, stated that without their lawyer, said that the family would not be able to come without Mr. Akbar. He also told The Guardian that the State Department had not given a reason

“I don’t know why the State Department has taken this action, but I think it’s extremely important that when it comes to a national security matter like drone attacks, we hear not only from the proponents of these attacks, but also from the victims,” Grayson said.

“We have a chronic problem in Congress that when the administration is involved in one side of the issue, we rarely hear about the other side of the issue.

“This is true with regard to NSA domestic spying. This is true with regard to proposed military intervention in Syria. And it’s also true with regard to the drone attacks in Pakistan and in Yemen.”

He added: “I think Congress and the American people simply need to hear both sides of the story, and that’s why we invited these witnesses to come and testify.”